Hydraulic or pneumatic controlled two stage slide valve

ABSTRACT

A fluid-operated, in particular hydraulically or pneumatically controllable, two-stage slide valve arrangement including an outlet stage arrangement for alternately communicating in flow relationship an outflow conduit with a pressure conduit and return flow conduit of a fluid-operated system is described and comprises a sleeve valve member having opposed end faces and respective coaxially extending displacement piston member acting upon each end face of said sleeve valve member, with the effective cross-sectional area of both said displacement piston members differing from one another, the outlet stage arrangement alternately connecting said outflow conduit with said pressure conduit and said return flow conduit when the displacement piston member with the smaller effective cross-sectional area is continuously impinged by a predetermined pressure of a fluid medium delivered by said pressure conduit. A forwardly arranged control stage arrangement alternately couples the other displacement piston member with the larger effective crosssectional area to the pressure conduit and the return flow conduit, said control stage arrangement including a first diaphragm means for coupling the displacement piston member of larger effective cross-sectional area of the outlet stage arrangement with the pressure conduit, and a second diaphragm means for coupling such displacement piston member of larger cross-sectional area with the return flow conduit. Both diaphragm means have an opening and at least one valve means serves for alternately closing and opening at least one opening of one of said diaphragm means, the valve means includes at least one toand-fro movable valve body member cooperating with said one diaphragm means and a valve membrane for moving said valve body member. There is also means for selectively operating the valve membrane and thus said valve body member for closing and opening at least said one opening of said one diaphragm means.

limited States Patent Furrer [4 June 27, 1972 [54] HYDRAULIC 0RPNEUMATIC CONTROLLED TWO STAGE SLIDE VALVE [72] inventor: 73] Assignee:Contraves AG, Zurich, Switzerland 22 Filed: Jan. 7, 1971 21 Appl.N0.:104,555

Eduard Furrer, Zurich, Switzerland Primary ExaminerAlan Cohan AssistantExaminerWilliam H. Wright Attorney-Werner W. Kleeman [5 7] ABSTRACT Afluid-operated, in particular hydraulically or pneumaticallycontrollable, two-stage slide valve arrangement including an outletstage arrangement for alternately communicating in flow relationship anoutflow conduit with a pressure conduit and return flow conduit of afluid-operated system is described and comprises a sleeve valve memberhaving opposed end faces and respective coaxially extending displacementpiston member acting upon each end face of said sleeve valve member,with the effective cross-sectional area of both said displacement pistonmembers difiering from one another, the outlet stage arrangementalternately connecting said outflow conduit with said pressure conduitand said return flow conduit when the displacement piston member withthe smaller efiective cross-sectional area is continuously impinged by apredetermined pressure of a fluid medium delivered by -said pressureconduit. A forwardly arranged control stage arrangement alternatelycouples the other displacement piston member with the larger efiectivecross-sectional area to the pressure conduit and the return flowconduit, said control stage arrangement including a first diaphragmmeans for coupling the displacement piston member of larger eflectivecross-sectional area of the outlet stage arrangement with the pressureconduit, and a second diaphragm means for coupling such displacementpistonmember of larger cross-sectional area with the return flowconduit. Both diaphragm means have an opening and at least one valvemeans serves for alternately closing and opening atleast one opening ofone of said diaphragm means, the valve means includes at least onetoand-fro movable valve body member cooperating with said one diaphragmmeans and a valve membrane for moving said valve body member. There isalso means for selectively operating the valve membrane and thus saidvalve body member for closing and opening at least said one opening ofsaid one diaphragm means.

4 Claims, 2 Drawing Figures PNENTEDJUM? I372 SHEET 1 BF 2 om mm NVENTO)? uam) Fad/213R HYDRAULIC OR PNEUMATIC CONTROLLED TWO STAGE SLIDEVALVE BACKGROUND OF THE INVENTION The present invention relates to a newand improved fluidoperated, especially hydraulically or pneumaticallycontrollable two-stage slide valve arrangement for alternatelyoperatively communicate in flow relationship an outflow conduit with apressure conduit and return flow conduit of a fluidoperated system whena respective coaxially extending displacement piston member acts uponeach end face of a sleeve valve or slide valve piston member, theeffective cross-sectional areas of such displacement piston membersdiffering from one another. In the system of the invention the displacement piston member with the smaller effective cross-sectional area iscontinuously impinged with a predetermined pressure of the fluid mediumdelivered by the pressure conduit, and a forwardly connected controlstage alternately connects the other displacement piston member havingthe larger effective cross-sectional area with the pressureconduit andthe return flow conduit.

In known two-stage slide valve arrangements there are used both in theoutput or outflow stage arrangement as well as in the pro-stagearrangement slide valves or slide valve piston members for alternatelyconnecting and disconnecting conduits. Such slide valve arrangementsmanifest themselves by virtue of their very short switching times,typically several milliseconds. These short switching times areespecially attained by virtue of the fact that displacement of the slidevalves within their receiving bores is not impeded by any sealingelements. Any time-delay which might arise owing to contamination orsoiling of the system or the hydraulic adhesion" effect at the sleevevalve or slide valve piston member of the outlet stage is negligiblesince, by virtue of the high operating pressures, large forces act uponthis slide valve. However, in the preliminary or pre-stage arrangementthere are oftentimes available only very small control pressures for theto-and-fro movement of the sleeve valve, so that during longerinterruptions in the switching operation it is indeed possible fordelays in the switching process to occur, which delays are brought aboutby the hydraulic adhesion effect prevailing at the sleeve valve of thepre-stage arrangement.

SUMMARY OF THE INVENTION Accordingly, there is still present in the arta need for an improved fluid-operated, especially hydraulically orpneumatically controllable twostage slide valve arrangement, which isnot associated with the aforementioned drawbacks of the prior artsystems. Therefore, a primary objective of the instant invention is theprovision of a slide valve arrangement of the mentioned type whicheffectively and reliably overcomes the previously discussed drawbacks ofthe prior art equipment and fulfills the existing need in the art.

Another and more specific object of the present invention relates to theprovision of a novel type of hydraulically or pneumatically controlledtwo-stage slide valve arrangement possessing extremely short switchingtimes. I

Yet further significant object of the present invention relates to animproved fluid-operated slide valve arrangement which not only manifestsitself through short switching times, especially at the pre-stagearrangement thereof, but one which is also relatively simple inconstruction, economical to manufacture, not readily subject tobreakdown, extremely reliable in operation, and requiring a minimum ofmaintenance and servicing.

Now in order to implement these and still further objecm of theinvention, which shall'become more readily apparent as the descriptionproceeds, the inventive fluid-operated slide valve arrangement ismanifested by the features that the displacement piston memberpossessing the larger effective cross-sectional area of the outlet oroutput stage is coupled by a first diaphragm means with the pressureconduit or line and by a second'diaphragm means with the return flowline, that at least the opening of one diaphragm means is alternatelyclosed and opened by at least one valve unit, that the to-and-fromovement of at least one valve closing member of the valve unit isalternately subjected to an underpressure or overpressure through theaction of at least one valve membrane owing to the action offluid-operated, e.g., pneumatic or hydraulic control means which bound arespective hollow compartment at the respective outer faces or side ofsaid at least one valve membrane, in order to close and open at leastthe opening of said one diaphragm means.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be betterunderstood and objects other than those set forth above will becomeapparent when consideration is given to the following detaileddescription thereof. Such description makes reference to the annexeddrawings wherein:

FIG. 1 is a longitudinal sectional view of a two-stage slide valvearrangement of the present invention incorporating a closing mechanismfor one of the diaphragms or orifice plates;

FIG. 2 is a modified form of inventive two-stage slide valvearrangement, again in longitudinal sectional view, illustrating aclosing mechanism for both diaphragms or orifice plates.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Describing now thedrawings, in the exemplary embodiment of inventive slide valvearrangement depicted in FIG. 1 there is provided a housing unit 1containing a longitudinally extending bore 10 for slidably receivingsleeve valve or slide valve piston member 4. Additionally this housingunit 1 is provided with the annular groove means 11, the pressureconduits or lines 501 and 502, the return flow conduit or line 503communicating with the bore 10, as well as thereturn flow conduit orconnection R12, the outlet or outflow connection A13 and the pressureconduit or connection D14 which is also coupled with the pressureconduit 502. A first diaphragm or orifice plate 6 is installed in thepressure line 502, as shown.

Additionally it will be observed that at each side of the housing orhousing unit 1 there is provided a cover member 2 and 3, respectively,equipped with the bores 20 and 30 respectively, and portions of theconduits or lines 501 and 502 respectively, the .cover members 2 and 3being sealingly mounted at the ends of the housing 1. The bores 20 and30 possess a cross-sectional area which difiers from one another andserve as'guide means for the displacement piston members 22 and 32respectively, which likewise possess different effective cross-sectionalareas from one another and smaller than that of the sleeve valve 4.Displacement piston members 22 and 32 act upon the end faces or surfacesof the sleeve valve or slide valve piston member 4.

The slide valve piston member 4 additionally is equipped with twoannular grooves 41 and 42 and an axial extending bore 40 which widens atboth ends 44, as shown. A transversely extending opening or aperture 43communicates the axially extending bore 40 with the annular groove 41.At the widened end portions 44 of the bore 40 there is inserted arespective square member 45, or equivalent structure, against which actthe associated displacement piston member 22 or 32 respectively. Sincethe square member 45 does not completely fill out the associated hollowcylindrical widened portion 44 there continuously prevails a connectionbetween the left and/or right portions of the bore 10 located externallyof the slide valve piston member 4 and the return flow conduit orconnection R12, so that any leakage fluid medium flowing-out at thelocation of the displacement piston members 22 and 32, or else at someother location of the pressurized system, does not impair the to-and-fromovement of the slide valve piston member 4, rather can flow back to thereturn flow conduit R12.

A socket member 5 of the housing unit 1 contains the conduit 501, theconduit 18 leading to a separate return flow conduit R12, the widenedportions or chamber recesses 17 and 50, a guide bore or aperture for thevalve rod 83, the second diaphragm or orifice plate 7 having thediaphragm opening 71, and the return flow conduit 503.

The cover or cover portion 9 of the socket 5 is equipped with theconnection or port 24 and the widened portion or chamber recess 17. Avalve diaphragm or membrane 120 of a valve unit 8 divides the chamber 17into hollow compartments 17' and 25. The rod member 83 which is rigidlyconnected with a valve closure body 80 is displaceably guided in thesocket 5 and at the valve plate 88 rigidly connected with the valvediaphragm 120, so that there is ensured for a clean closing action ofthe diaphragm opening 71. The output stage of the slide valvearrangement can be actuated by a hydraulic or pneumatic system, hereshown as consisting of a pump P equipped with the pressurized conduit orline D and the return flow conduit or line R.

With the aid of the likewise hydraulically or pneumatically actuatedpre-stage it is possible to couple the displacement piston member 22possessing the larger effective cross-sectional area either only withthe pressurized conduit D via a small opening 61 of the diaphragm 6 oralso, however, via a larger opening 71 of the diaphragm 7 with thereturn flow line or conduit R. The displacement piston member 32, justas is the case with the pressure conduit D14, always remains coupledwith the pressure line or conduit D. In the illustrated position thevalve membrane or diaphragm 120 is deformed via the connection 24 withthe aid of a pneumatic or hydraulic fluid medium, indicated at D1, insuch a manner that the valve closure body 80 keeps the valve ordiaphragm opening 71 closed. Consequently, the pressure of the fluidmedium in the pressure connection or conduit D14 acts upon thedisplacement piston member 22 and maintains the slide valve pistonmember 4 in the illustrated position. The connection A13 is coupled viathe annular groove 41 with the return flow connection R12.

If the hollow compartment 25 or the valve diaphragm 120 is relieved ofthe pressure action schematically indicated at D1, then the diaphragmopening 71 is released by the valve closure body 80 so lower pressureconditions can prevail at the displacement piston member 22. Now thedisplacement piston member 32 displaces the slide valve piston member orsleeve valve 4 until it contacts against the cover member 2 at the leftside of the system shown in FIG. 1. Hence, the outlet connection A13 iscoupled in flow communication with the pressure connection D14 via theannular groove 42, and is cut off or separated from the return flowconduit R12. The leakage fluid medium flowing through the smalldiaphragm opening 61 of the diaphragm or orifice plate 6 is deliveredvia the larger diaphragm opening 71 to the conduit 503, and thereforedelivered back to the return flow arrangement R12, R. The channel 18connects the hollow compartment 17' with a separate return flow line,schematically indicated at R12, which also renders possible adisturbance-free functioning of the valve diaphragm 120 even if leakagefluid medium penetrates into such hollow compartment.

Considering now the modified version of slide valve arrangement asdepicted in FIG. 2, there it will be recognized that at the first orpre-stage thereof a respective valve diaphragm or membrane 120 and 130separates the chambers 100 and 200 into the hollow compartments 17, 25and 16, 35 respectively. By means of the inflow ports or connections 34and 24, it is possible to deform the diaphragms 120 and 130,respectively, through the action of a pneumatic or hydraulic fluidmedium in such a manner that the valve closure body member 80 carriesout reciprocating or to-and-fro movements. These movements of the valvediaphragms 120 and 130 are transmitted by means of the rod 83, the shaft84 secured by screws 85 to such rod, the connection piece 86 rotatablymounted at a pin or shaft member 82 and provided at both sides withslots, and via a further shaft 81 secured to the connection piece 86, tothe valve closure body member 80. Due to these to-and-fro movements thediaphragm openings 61 and 71 of the diaphragm 6 and 7, respectively, arealternately closed and opened. The bore 10 in the exemplary embodimentof slide valve arrangement under consideration, is enlarged by theannular grooves 11, 141 and 142. The displacement piston member 432 isslidably arranged at a noncontinuous or one-end closed axial bore 430 ofthe slide valve member 4, this displacement piston member 432 beingcontinuously connected with the pressure conduit or connection D14through the agency of the annular grooves 42 and 142 as well as theopening or aperture 446.

In the illustrated position of the valve closure body member 80, thepressure of the fluid medium moving through connection D14 acts via thechannel 502, the diaphragm opening 61 and the channel 501 upon thedisplacement piston member 22 possessing the larger effectivecross-sectional area. The sleeve valve or slide valve piston member 4 isthus maintained in the illustrated position. The outlet connection A13is coupled via the annular grooves 11, 41 and 141 with the return flowconduit R12. If the diaphragm 130 is pneumatically or hydraulicallysubjected to pressure via port 34, then, the diaphragm opening 61 isclosed by the valve closure body and the diaphragm opening 71 is opened.The channel 501 is cut off or separated from the channel 502 and bymeans of the chamber recess or widened portion 19, the diaphragm opening71, the channel 503 and the annular grooves 41 and 141 this channel 501is connected with the return flow line R120. The relieved displacementpiston member 22 is pushed back by the slide valve piston member 4 untilcontacting the stop at the left of the bore 20, this slide valve pistonmember 4 being moved by the forces generated in the axial bore 430 byvirtue of the pressure. The outlet connection A13 is thus separated fromthe return flow connection R12 and coupled via the annular grooves 11,42 and 142 with the pressure conduit or connection D14. Any escapingpneumatic or hydraulic leakage fluid medium which has collected at thebore 10, to the left and/or right of the slide valve piston member 4, isreturned via the longitudinal bore 400 in such slide valve piston member4 back to the return flow conduit R12. The slide valve arrangementalways remains functional. The channel 18 connects both hollowcompartments 16 and 17 with one another and to the outside, andtherefore renders possible also during escape of any leakage fluidmedium, a disturbance-free functioning of the membranes or diaphragmsand in the hollow compartments 16 and 17.

While there is shown and described present preferred embodiments of theinvention, it is to be distinctly understood that the invention is notlimited thereto but may be otherwise variously embodied and practicedwithin the scope of the following claims.

Accordingly, what is claimed is:

1. A fluid-operated, in particular hydraulically or pneumaticallycontrollable, two-stage slide valve arrangement including an outletstage arrangement for alternately communicating in flow relationship anoutflow conduit with a pressure conduit and return flow conduit of afluid-operated system, comprising said outlet stage arrangementembodying a slide valve housing provided with an outflow conduit, apressure conduit, and a return flow conduit, a sleeve valve memberhaving opposed end faces, a respective coaxially extending displacementpiston member acting upon each end face of said sleeve valve member, theeffective cross-sectional area of both said displacement piston membersdifferring from one another, said outlet stage arrangement alternatelyconnecting said outflow conduit with said pressure conduit and saidreturn flow conduit when the displacement piston member with the smallereffective cross-sectional area is continuously impinged by apredetermined pressure of a fluid medium delivered by said pressureconduit, and a forwardly arranged control stage arrangement foralternately coupling the other displacement piston member with thelarger effective cross-sectional area to said pressure conduit and saidreturn flow conduit, said control stage arrangement including a firstdiaphragm means for coupling the displacement piston member of largereffective cross-sectional area of the outlet stage arrangement with thepressure conduit, and a second diaphragm means for coupling suchdisplacement piston member of larger cross-sectional area with thereturn flow conduit, both said diaphragm means each having an opening,at least one valve means for alternately closing and opening at leastone opening of one of said diaphragm means, said valve means includingat least one toand-fro movable valve body member cooperating with saidone diaphragm means and a valve membrane for moving said valve bodymember, means for selectively operating said valve membrane and thussaid valve body member for closing and opening at least said one openingof said one diaphragm means.

2. A fluid-operated, in particular hydraulically or pneumaticallycontrollable two-stage valve arrangement as defined in claim 1, whereinthe cross-sectional area of the opening-of said first diaphragm means issmaller than the cross-sectional area of the opening of said seconddiaphragm means, said valve closure body member opening and closing theopening of said second diaphragm means.

3. A fluid-operated, in particular hydraulically or pneumaticallycontrollable slide valve arrangement as defined in claim 1, wherein twodiaphragm means and a valve means with two valve membranes are providedand arranged in such a manner that alternately said valve membranesunder the action of said operating means move said valve closure bodymember toand-fro for selectively closing and opening said respectiveopenings of said two diaphragm means.

4. A fluid-operated two-stage slide valve arrangement comprising anoutlet stage arrangement embodying a slide valve housing provided withan outflow conduit, a pressure conduit, and a return flow conduit, asleeve valve member having opposed end faces, a respective coaxiallyextending displacement piston member acting upon each end face of saidsleeve valve member, the effective cross-sectional area of both saiddisplacement piston members differing from one another, said outletstage arrangement alternately connecting said outflow conduit with saidpressure conduitand said return flow conduit when the displacementpiston member with the smaller effective cross-sectional area iscontinuously impinged by a predetermined pressure of a fluid mediumdelivered by said pressure conduit, a control stage arrangement foralternately coupling the other displacement piston member with thelarger effective cross-sectional area to said pressure conduit and saidreturn flow conduit, said control stage arrangement embodying a firstmeans for coupling the outflow stage arrangement by means of thedisplacement piston member of larger effective cross-sectional area withthe pressure conduit, and a second means for coupling the outflow stagearrange ment by means of the displacement piston member with the largercross-sectional area with the return flow conduit, said first and secondcoupling means each having an opening, at least one valve means foralternately closing and opening at least one opening of one of saidcoupling means.

Patent No. 3,672,399 Dated June 27, 1972 M e EYDUARD FURRERY iscertified that errhr 'appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Cancel theillustrative figure of-drawing on the cever sheet andsubstitute the attached figure of drawing.

Signed and sealed this 16th day efJulyil974.

(SEAL) Attest:

MCCOY M. GIBSON, JR. C. MARSHALL DANN Attesting Officer 7 Commissionerof Patents- FORM po'wso USCOMM-DC bean-Pea ".5. GOVERNMENT PRINTINGDFFICE 1 IS 0-356-334,

PATENT NO'. 5, 72,399 -2- as a 9120

1. A fluid-operated, in particular hydraulically or pneumaticallycontrollable, two-stage slide valve arrangement including an outletstage arrangement for alternately communicating in flow relationship anoutflow conduit with a pressure conduit and return flow conduit of afluid-operated system, comprising said outlet stage arrangementembodying a slide valve housing provided with an outflow conduit, apressure conduit, and a return flow conduit, a sleeve valve memberhaving opposed end faces, a respective coaxially extending displacementpiston member acting upon each end face of said sleeve valve member, theeffective cross-sectional area of both said displacement piston membersdifferring from one another, said outlet stage arrangement alternatelyconnecting said outflow conduit with said pressure conduit and saidreturn flow conduit when the displacement piston member with the smallereffective cross-sectional area is continuously impinged by apredetermined pressure of a fluid medium delivered by said pressureconduit, and a forwardly arranged control stage arrangement foralternately coupling the other displacement piston member with thelarger effective cross-sectional area to said pressure conduit and saidreturn flow conduit, said control stage arrangement including a firstdiaphragm means for coupling the displacement piston member of largereffective cross-sectional area of the outlet stage arrangement with thepressure conduit, and a second diaphragm means for coupling suchdisplacement piston member of larger cross-sectional area with thereturn flow conduit, both said diaphragm means each having an opening,at least one valve means for alternately closing and opening at leastone opening of one of said diaphragm means, said valve means includingat least one to-and-fro movable valve body member cooperating with saidone diaphragm means and a valve membrane for moving said valve bodymember, means for selectively operating said valve membrane and thussaid valve body member for closing and opening at least said one openingof said one diaphragm means.
 2. A fluid-operated, in particularhydraulically or pneumatically controllable two-stage valve arrangementas defined in claim 1, wherein the cross-sectional area of the openingof said first diaphragm means is smaller than the cross-sectional areaof the opening of said second diaphragm Means, said valve closure bodymember opening and closing the opening of said second diaphragm means.3. A fluid-operated, in particular hydraulically or pneumaticallycontrollable slide valve arrangement as defined in claim 1, wherein twodiaphragm means and a valve means with two valve membranes are providedand arranged in such a manner that alternately said valve membranesunder the action of said operating means move said valve closure bodymember to-and-fro for selectively closing and opening said respectiveopenings of said two diaphragm means.
 4. A fluid-operated two-stageslide valve arrangement comprising an outlet stage arrangement embodyinga slide valve housing provided with an outflow conduit, a pressureconduit, and a return flow conduit, a sleeve valve member having opposedend faces, a respective coaxially extending displacement piston memberacting upon each end face of said sleeve valve member, the effectivecross-sectional area of both said displacement piston members differingfrom one another, said outlet stage arrangement alternately connectingsaid outflow conduit with said pressure conduit and said return flowconduit when the displacement piston member with the smaller effectivecross-sectional area is continuously impinged by a predeterminedpressure of a fluid medium delivered by said pressure conduit, a controlstage arrangement for alternately coupling the other displacement pistonmember with the larger effective cross-sectional area to said pressureconduit and said return flow conduit, said control stage arrangementembodying a first means for coupling the outflow stage arrangement bymeans of the displacement piston member of larger effectivecross-sectional area with the pressure conduit, and a second means forcoupling the outflow stage arrangement by means of the displacementpiston member with the larger cross-sectional area with the return flowconduit, said first and second coupling means each having an opening, atleast one valve means for alternately closing and opening at least oneopening of one of said coupling means.